A body is falling freely under the action of gravity alone in vacuum. Which of the following quantities remain constant during the fall ?

Options

A. Kinetic energy
B. Potential energy
C. Total mechanical energy
D. Total linear momentum

Answer

C

Explanation

As the body is falling freely under gravity, the potential energy decreases and kinetic energy increases but total mechanical energy (PE + KE) of the body and earth system will be constant as external force on the system is zero.